it strikes me that a lot of the best stories use their dynamic as a mirror for each other's unresolved issues. Isogai is so focused on being the responsible one, the provider, and sometimes that reads as a fear of being a burden. Maehara, with his laid-back facade covering his own insecurities, can challenge that by needing him in non-transactional ways. A fic I read had Maehara getting seriously injured, not in a dramatic way, but from a stupid, mundane accident, and Isogai completely falling apart because his 'provider' role was useless—all he could do was wait and be emotionally present. That forced Isogai's growth from a 'carer' to someone who allows himself to be cared for. Meanwhile, Maehara learns to let someone see past the class clown act not because of a grand confession, but through the quiet, daily vulnerability of recovery. Their growth isn't about fixing each other, but about creating a space where their respective coping mechanisms can soften.
Some authors take the opposite route, focusing on their canon competitiveness as a catalyst. Stories that pit them in academic or physical rivalry, but with the underlying tension shifting from 'I have to beat you' to 'I want to be worthy of you.' That angle explores growth through admiration rather than trauma bonding, which is a nice change of pace.